Race Condition Affecting bpftool package, versions *

Note: Versions mentioned in the description apply only to the upstream bpftool package and not the bpftool package as distributed by Centos. See How to fix? for Centos:7 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nf_tables: mark set as dead when unbinding anonymous set with timeout

While the rhashtable set gc runs asynchronously, a race allows it to collect elements from anonymous sets with timeouts while it is being released from the commit path.

Mingi Cho originally reported this issue in a different path in 6.1.x with a pipapo set with low timeouts which is not possible upstream since 7395dfacfff6 ("netfilter: nf_tables: use timestamp to check for set element timeout").

Fix this by setting on the dead flag for anonymous sets to skip async gc in this case.

According to 08e4c8c5919f ("netfilter: nf_tables: mark newset as dead on transaction abort"), Florian plans to accelerate abort path by releasing objects via workqueue, therefore, this sets on the dead flag for abort path too.

• https://access.redhat.com/security/cve/CVE-2024-26643
• https://git.kernel.org/stable/c/552705a3650bbf46a22b1adedc1b04181490fc36
• https://git.kernel.org/stable/c/406b0241d0eb598a0b330ab20ae325537d8d8163
• https://git.kernel.org/stable/c/5224afbc30c3ca9ba23e752f0f138729b2c48dd8
• https://git.kernel.org/stable/c/b2d6f9a5b1cf968f1eaa71085ceeb09c2cb276b1
• https://git.kernel.org/stable/c/291cca35818bd52a407bc37ab45a15816039e363
• https://git.kernel.org/stable/c/e2d45f467096e931044f0ab7634499879d851a5c
• https://git.kernel.org/stable/c/edcf1a3f182ecf8b6b805f0ce90570ea98c5f6bf
• https://git.kernel.org/stable/c/d75a589bb92af1abf3b779cfcd1977ca11b27033
• https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html